


Silverlight

by Destiny_in_the_Universe



Series: Kitten of Mine [2]
Category: Harry Potter - J. K. Rowling, Sherlock (TV)
Genre: Dementors, Fluff, Light Angst, Mycroft Being a Good Brother, Patronus, Protective Mycroft, Protective Siblings, Sibling Bonding
Language: English
Status: Completed
Published: 2018-12-23
Updated: 2018-12-23
Packaged: 2019-09-25 15:00:57
Rating: General Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 926
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/17123567
Author URL: https://archiveofourown.org/users/Destiny_in_the_Universe/pseuds/Destiny_in_the_Universe
Summary: Mycroft Holmes teaches his little sister how to perform a patronus





	Silverlight

**Author's Note:**

  * For [DrAloraBatlock](https://archiveofourown.org/users/DrAloraBatlock/gifts).



> Sherlie Holmes belongs to my good friend, Lory, or as she is known here, DrAloraBatlock. The use of her character is completely accepted, since I was given permission.

Mycroft cursed inwardly as he bolted forward, trying to run and make it back to the Hogwarts castle before he got seen again. Of course, out of all things, the faculty of the place had decided it would be quite beneficial for everyone to have dementors roaming the grounds. 

 

He hadn’t meant to be out at this hour, but the fact was that Sherlie, his first year little sister, had vanished from the premises and he begun to grow agitated, wondering what had happened to her. Mycroft snarled as he made it out, only to let out a startled gasp, eyes widened when he noticed the shape of the dementor further up ahead, close to Hogwarts and a smaller shape cowering down. 

 

“SHERLIE!” Mycroft howled as he noticed who it was, the Slytherin student racing, his wand held out in front of him. 

 

The young girl had her hands over her head, shaking badly. She, considering she was a first year, shouldn’t have to be going through this. 

 

“Get away from her!” Mycroft spat as he stepped in front of Sherlie, his little sister, and held out his wand steadily. He had to maintain his emotions cool. 

 

A patronus charm could only be performed with a very strong, happy memory, and he wouldn’t be able to focus if he was panicked and afraid over what would happen to the younger Holmes. 

 

The feeling of dread and fear washed over him, Mycroft hitching a breath as he felt he couldn’t move. Focus. Come on! Focus. 

 

“Expecto Patronum!” Mycroft suddenly yelled loudly, his eyes darkening sharply, as a silvery form erupted from his wand. The animal, taking resemblance of a red fox, pranced around, circling the dementor and slowly making it disappear. 

 

“Mycroft- Mycie!” The shouts of Sherlie could be faintly heard in the background.

 

Mycroft could barely listen on her voice, his knees buckling out of nowhere as he collapsed hard, his entire world going black. 

 

He awoke a while later, a soft groan escaping his lips. His eyes slowly opened to realize he was on one of the infirmary beds, his wand placed on the table beside him. What had happened? 

 

“Mycroft!” The whine of Sherlie echoed out. 

 

Mycroft let out a startled noise, not having much time to react as his little sister barreled into him. He carefully wrapped his arms around his kitten, the young Hogwarts wizard carefully bringing one hand up to brush her hair with his fingers. 

 

“I’m okay, little cat,” he cooed softly. 

 

“I thought… I thought you were-“ 

 

“No… hey, no, I’m okay. I’m okay.” 

 

Mycroft sat up, wincing a bit, but overall he was fine. He pulled Sherlie on the bed, keeping her in place as he rocked her gently, whispering words of comfort. 

 

“... Mycroft… that spell you did- what was it?” Sherlie asked curiously. 

 

Mycroft smiled at the sudden question, chuckling a bit in response. He enjoyed it when she asked him about things he’d learned in school and now that she was a student, he had a year before he graduated. 

 

“It’s the patronus charm. It works on happy, strong memories and takes the form of a silver animal or wisps of light depending on the strength of said wizard or witch.” 

 

Sherlie clung onto his every word, her eyes wide and interested in everything that her brother had to say. The two had been exceptionally close, even when they were children and for that, she had been happy, looking up to him for many different things. 

 

“Would you like to learn?” Mycroft asked her. He figured she’d need the spell, considering the brilliance of dementors at the school. What a lovely— sarcasm— idea. Hadn’t they learned the first time with Harry Potter and the previous generation of students? 

 

Sherlie squealed, giggling at the question. She purred softly when Mycroft nuzzled her gently. 

 

When Mycroft got discharged from the infirmary a couple days later, he took Sherlie to the Defense classroom and smiled warmly. He was determined to make sure she left knowing the spell to defend herself against those pesky creatures. 

 

“Alright, Sherlie, first thing is… you need to concentrate on a pure happy memory. It can’t be just any… it has to be a strong one that you can use to truly ward off the darkness.” 

 

Sherlie thought long and hard, before she suddenly brightened, nodding at Mycroft that she had one. 

 

“Once you have it set, then cast out the spell. Expecto. Patronum.” Mycroft instructed. 

 

The younger witch gave a small little giggle before she suddenly held out her wand casted firmly. 

 

“Expecto Patronum!” 

 

Only a wisp of silvery mist came out, causing Sherlie to pout in reply. She huffed before trying again, the mist becoming only slightly stronger. 

 

“You can do this, Sherlie! I know you can!” Mycroft gave her a bit of praise, encouraging his sister further. 

 

“Expecto Patronum!” 

 

Suddenly, a bright form filled the room, taking a dance all over the place. The animal was small yet fierce, a little kitten, coming to stop in front of Mycroft and nuzzling into the side of his cheek, before vanishing out of nowhere. 

 

“It’s perfect, kitten. What memory did you use?” 

 

Sherlie tilted her head then smiled up at her favorite sibling. 

 

“It was you. You make me happy,” she replied lightly as her brother stared at her with surprise and happiness written on his face. 

 

“Oh, Sherlie…” Mycroft whispered as he briefly pulled her into a hug, casting the patronus along with his little sister, the fox protecting his kitten from danger. 

**Author's Note:**

> My dearest Lory, I hope you enjoy this little Christmas present! It was a lot of fun to write and Merry Christmas, my friend, even if it is a bit early.


End file.
